1. Field of the Invention
The present invention relates to an image generation method for performing color conversion on an image.
2. Description of the Related Art
Users with any impairment in color vision wherein colors appear indistinguishable may find it difficult to identify material displayed on a display unit of a product or printed material.
Even users who do not have a problem in distinguishing between colors may be less able to distinguish between color tones. To address this issue, for example, the following techniques have been proposed.
Japanese Patent Laid-Open No. 2002-55671 describes a technique in which a portion of display data that is to be subjected to color conversion is determined so that color conversion can be performed only on the determined portion. This technique allows color conversion only for a desired portion of display data while preventing color conversion for an unnecessary portion to display an image having desired high reproducibility, such as a photograph.
Japanese Patent Laid-Open No. 2006-509223 (Translation of PCT Application) describes a technique in which color vision impairment information is input by a user and color conversion is performed according to the input information. The color vision impairment information includes information indicating what color is indistinguishable to the user, and information indicating how indistinguishable that color is.
The technique described in Japanese Patent Laid-Open No. 2002-55671, however, has a problem in that performing color conversion to provide easy-to-read material for each user is not straightforward. The severity of color vision impairment differs from person to person, and it is difficult to uniquely determine whether to perform color conversion.
In the technique described in Japanese Patent Laid-Open No. 2006-509223 (Translation of PCT Application), a user inputs color vision impairment information through an operation unit. The user does not specify a desired visual representation but only inputs color vision impairment information. Therefore, it is not easy for a user who does not understand their vision impairment characteristic to input color vision impairment information. In some cases, conversion of indistinguishable colors into desired colors may fail to be achieved.
In particular, users having difficulty in identifying a particular color may not be able to identify text depending on a pair of a background color and a text color. Thus, for example, if a message for such users is displayed on a display screen, the users may not be able to identify the message and may perform an incorrect operation.